Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh dai » thanh hai, thanh tai, thanh dat
vay luan » ly luan, von luan, bai luan
duoc ban » duc ban, quoc ban, buoc ban
cua viet » ca viet, hoa viet, cua vat
sach ky » sach y, sach ty, sach kem
nang ma » tang ma, sang ma, nang cao
va luat » va thuat, cua luat, dan luat
sac ky » cac ky, sai ky
ma hoi » mai hoi, xa hoi, ma hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sac ky)) nang ma hoi. lieu ((va luat) OR (vay luan)) duoc ban thanh dai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang ma hoi. lieu ((va luat) OR (vay luan)) duoc ban thanh dai cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang ma hoi. lieu ((va luat) OR (vay luan)) duoc ban thanh dai cua viet*".